Remarks

Ms5611
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

The MS5611 is a barometer and temperature sensor that communicates over I2C or SPI up to 20Mhz. Operating range: 10 to 1200 mbar, -40 to +85 °C.

Code Example

Ms5611 sensor;

public override Task Initialize()
{
    Resolver.Log.Info("Initializing...");

    sensor = new Ms5611(Device.CreateI2cBus());

    var consumer = Ms5611.CreateObserver(
        handler: result =>
        {
            Resolver.Log.Info($"Observer: Temp changed by threshold; new temp: {result.New.Temperature?.Celsius:N2}C, old: {result.Old?.Temperature?.Celsius:N2}C");
        },
        filter: result =>
        {
            //c# 8 pattern match syntax. checks for !null and assigns var.
            if (result.Old is { } old)
            {
                return (
                (result.New.Temperature.Value - old.Temperature.Value).Abs().Celsius > 0.5
                &&
                (result.New.Pressure.Value - old.Pressure.Value).Millibar > 0.5
                );
            }
            return false;
        }
    );
    sensor.Subscribe(consumer);

    sensor.Updated += (sender, result) => {
        Resolver.Log.Info($"  Temperature: {result.New.Temperature?.Celsius:N2}C");
        Resolver.Log.Info($"  Pressure: {result.New.Pressure?.Millibar:N2}mbar ({result.New.Pressure?.Pascal:N2}Pa)");
    };

    return Task.CompletedTask;
}

public async override Task Run()
{
    var conditions = await sensor.Read();
    Resolver.Log.Info("Initial Readings:");
    Resolver.Log.Info($" Temperature: {conditions.Temperature?.Celsius:N2}C");
    Resolver.Log.Info($" Pressure: {conditions.Pressure?.Bar:N2}hPa");

    sensor.StartUpdating(TimeSpan.FromSeconds(1));
}

Sample project(s) available on GitHub

Wiring Example

To wire a Ms5611 to your Meadow board, connect the following:

Ms5611	Meadow Pin
GND	GND
SCL	D08 (SCL)
SDA	D07 (SDA)
VCC	3V3

It should look like the following diagram:

Characteristic	Locus
Inheritance	System.Object > Ms5611
Implements	ITemperatureSensor IBarometricPressureSensor
Namespace	Meadow.Foundation.Sensors.Atmospheric
Assembly	Ms5611.dll

Syntax

public class Ms5611 : ByteCommsSensorBase<(Units.Temperature? Temperature, Pressure? Pressure)>, ITemperatureSensor, IBarometricPressureSensor

Constructors

Ms5611(II2cBus, Byte, Ms5611.Resolution)

Connect to the Ms5611 using I2C

Declaration

public Ms5611(II2cBus i2cBus, byte address = null, Ms5611.Resolution resolution = default(Ms5611.Resolution))

Parameters

Type	Name	Description
II2cBus	i2cBus	The I2C bus connected to the device
System.Byte	address	I2c address - default is 0x5c
Ms5611.Resolution	resolution

Properties

Pressure

The pressure, in hectopascals (hPa), from the last reading. 1 hPa is equal to one millibar, or 1/10th of a kilopascal (kPa)/centibar

Declaration

public Pressure? Pressure { get; }

Property Value

Type	Description
System.Nullable<Pressure>

Temperature

The temperature, in degrees celsius (°C), from the last reading

Declaration

public Units.Temperature? Temperature { get; }

Property Value

Type	Description
System.Nullable<Units.Temperature>

Methods

RaiseEventsAndNotify(IChangeResult<(Nullable<Units.Temperature> Temperature, Nullable<Pressure> Pressure)>)

Raise events for subcribers and notify of value changes

Declaration

protected override void RaiseEventsAndNotify(IChangeResult<(Units.Temperature? Temperature, Pressure? Pressure)> changeResult)

Parameters

Type	Name	Description
IChangeResult<System.ValueTuple<System.Nullable<Units.Temperature>, System.Nullable<Pressure>>>	changeResult	The updated sensor data

ReadSensor()

Reads data from the sensor

Declaration

protected override Task<(Units.Temperature? Temperature, Pressure? Pressure)> ReadSensor()

Returns

Type	Description
Task<System.ValueTuple<System.Nullable<Units.Temperature>, System.Nullable<Pressure>>>	The latest sensor reading

Reset()

Reset the MS5611

Declaration

public void Reset()

Events

PressureUpdated

Pressure changed event

Declaration

public event EventHandler<IChangeResult<Pressure>> PressureUpdated

Event Type

Type	Description
EventHandler<IChangeResult<Pressure>>

TemperatureUpdated

Temperature changed event

Declaration

public event EventHandler<IChangeResult<Units.Temperature>> TemperatureUpdated

Event Type

Type	Description
EventHandler<IChangeResult<Units.Temperature>>